This invention relates to a blowout protector for use in oil well tubing at a well head and the like.
Included among objects of the invention are the provision of a simple, safe and versatile blowout protector which provides an effective seal against blowouts; which can be operated from a safe remote location using air pressure, bottled gas, hydraulic pressure or the like; which is quick closing and of compact size; which can be used by service rigs or workover rigs for added safety; which is of simple construction for easy maintenance and economy of manufacture; and which has a minimum of moving parts for reliable operation.
In accordance with the invention, a blowout protector comprises a flatish box-like housing having top and bottom plates, and end and side plates defining a sealed internal chamber, aligned openings in the top and bottom plates for connection to well tubing, a closure plate slidable piston-wise in said chamber between respective open and closed positions toward respective ends of the chamber, the closure plate having an opening formed therethrough adapted to align with the openings in the top and bottom plates when the closure plate is in the open position to allow well fluid to flow through the tubing, the closure plate forming a barrier to flow through the tubing when in the closed position, and the housing including fluid pressure inlet and outlet ports at opposite ends of the housing for the introduction and exhaust of pressure fluid to and from the chamber to move the closure plate piston-wise between the open and closed positions.
Preferably, the top and bottom plates are provided with internal annular seals around the respective openings to seal against the upper and lower faces of the closure plate and duct means may be provided in the housing and through the closure plate to pressurize at least one of the seals (the one on the high pressure side of the housing) in the closed position of the closure plate to provide additional protection against escape of well fluids. The closure plate itself may also be provided with ring or lip-type seals at its respective ends.
These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.